var Base64 = {
	// private property
	_keyStr: 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=',
	// public method for encoding

	encode: function (input) {
		var output = '';
		var chr1, chr2, chr3, enc1, enc2, enc3, enc4;
		var i = 0;

		input = Base64._utf8_encode(input);

		while (i < input.length) {
			chr1 = input.charCodeAt(i++);
			chr2 = input.charCodeAt(i++);
			chr3 = input.charCodeAt(i++);

			enc1 = chr1 >> 2;
			enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
			enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
			enc4 = chr3 & 63;

			if (isNaN(chr2)) {
				enc3 = enc4 = 64;
			} else if (isNaN(chr3)) {
				enc4 = 64;
			}

			output = output + this._keyStr.charAt(enc1) + this._keyStr.charAt(enc2) + this._keyStr.charAt(enc3) + this._keyStr.charAt(enc4);
		} // Whend

		return output;
	}, // End Function encode
	// public method for decoding

	decode: function (input) {
		var output = '';
		var chr1, chr2, chr3;
		var enc1, enc2, enc3, enc4;
		var i = 0;

		input = input.replace(/[^A-Za-z0-9\+\/\=]/g, '');
		while (i < input.length) {
			enc1 = this._keyStr.indexOf(input.charAt(i++));
			enc2 = this._keyStr.indexOf(input.charAt(i++));
			enc3 = this._keyStr.indexOf(input.charAt(i++));
			enc4 = this._keyStr.indexOf(input.charAt(i++));

			chr1 = (enc1 << 2) | (enc2 >> 4);
			chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
			chr3 = ((enc3 & 3) << 6) | enc4;

			output = output + String.fromCharCode(chr1);

			if (enc3 !== 64) {
				output = output + String.fromCharCode(chr2);
			}

			if (enc4 !== 64) {
				output = output + String.fromCharCode(chr3);
			}
		} // Whend

		output = Base64._utf8_decode(output);
		return output;
	}, // End Function decode
	// private method for UTF-8 encoding

	_utf8_encode: function (string) {
		var utftext = '';
		string = string.replace(/\r\n/g, '\n');

		for (var n = 0; n < string.length; n++) {
			var c = string.charCodeAt(n);

			if (c < 128) {
				utftext += String.fromCharCode(c);
			} else if (c > 127 && c < 2048) {
				utftext += String.fromCharCode((c >> 6) | 192);
				utftext += String.fromCharCode((c & 63) | 128);
			} else {
				utftext += String.fromCharCode((c >> 12) | 224);
				utftext += String.fromCharCode(((c >> 6) & 63) | 128);
				utftext += String.fromCharCode((c & 63) | 128);
			}
		} // Next n

		return utftext;
	}, // End Function _utf8_encode
	// private method for UTF-8 decoding

	_utf8_decode: function (utftext) {
		var string = '';
		var i = 0;
		var c, c1, c2, c3;
		c = c1 = c2 = 0;

		while (i < utftext.length) {
			c = utftext.charCodeAt(i);

			if (c < 128) {
				string += String.fromCharCode(c);
				i++;
			} else if (c > 191 && c < 224) {
				c2 = utftext.charCodeAt(i + 1);
				string += String.fromCharCode(((c & 31) << 6) | (c2 & 63));
				i += 2;
			} else {
				c2 = utftext.charCodeAt(i + 1);
				c3 = utftext.charCodeAt(i + 2);
				string += String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63));
				i += 3;
			}
		} // Whend

		return string;
	}, // End Function _utf8_decode
};

export { Base64 };
